I. Field of the Invention
This invention relates to enolic monoether and diether of adipic dialdehyde and the method for preparing the same.
II. Description of the Prior Art
Cope rearrangement is a well known reaction for the rearrangement of 1,5-hexadienic compounds. In a special situation when the 1,5-hexadienic compound is substituted at the 3 or possibly the 4 position with a hydroxyl group, the normal Cope rearrangement is modified because the rearrangement product, which would be an enol, cannot exist alone and rearranges itself into a corresponding carboxylic derivative. The term "Oxy-Cope Rearrangement" has been proposed to describe this variant of the general reaction (see for example J. Am. Chem. Soc., 1964, 86, pp. 5017- 5018). In addition, it is known that when the rearrangement is carried out with a disecondary 1,5-hexadiene-3,4-diol, the normal product of Oxy-Cope rearrangement which would be an adipic dialdehyde, is not isolatable since it is cyclized immediately by internal crotonization into a cyclopentenic aldehyde (see for example Ann. Chim. 1934, 1,p. 55 C.R. Acad. Sc. Paris 1966, 262, page 567 - series C).
Such an evolution is not unexpected because the extraordinary instability of the adipic dialdehyde has long been recognized. The instability of the adipic dialdehyde is due to the easiness of its structure to cyclize by internal aldolization or crotonization, for example, even during simple heating of their aqueous solutions. This instability coupled with the fact that there exists no economic process for making these compounds offer an explanation why these products up to now have not been industrially developed despite their particularly reactive dialdehyde structure. In fact, it is known that the dialdehydes are extremely valuable products because of their many applications particularly in the fields of textile dressings, in the paper industry, for chemical synthesis, for the preparation of polyacetals, as well as their known application as disinfectants, as bactericides and others.